Semiconductor nanocrystals, a method for coating semiconductor nanocrystals, and products including same

Abstract

A semiconductor nanocrystal that emits green light having a peak emission with a full width at half maximum of about 30 nm or less at 100° C. and a method of making coated semiconductor nanocrystals are provided. Materials and other products including semiconductor nanocrystals described herein and materials and other products including semiconductor nanocrystals prepared by a method described herein are also disclosed.

What is claimed is: 
     
       1. A semiconductor nanocrystal that emits green light having a peak emission with a full width at half maximum of about 30 nm or less at about 25° C. and at about 100° C., wherein the semiconductor nanocrystal has a solid state external quantum efficiency of at least 90% at a temperature of 90° C. or above. 
     
     
       2. A semiconductor nanocrystal in accordance with  claim 1  wherein the full width at half maximum at 100° C. is about 25 nm or less. 
     
     
       3. A semiconductor nanocrystal in accordance with  claim 1  wherein the semiconductor nanocrystal comprises a core having a first shell over at least a portion of the outer surface of the core and a second shell over at least a portion of the outer surface of the first shell. 
     
     
       4. A semiconductor nanocrystal in accordance with  claim 3  wherein the full width at half maximum at 100° C. is about 25 nm or less. 
     
     
       5. A semiconductor nanocrystal in accordance with  claim 3  wherein the core comprises a Group IIB element and a Group VI B element. 
     
     
       6. A semiconductor nanocrystal in accordance with  claim 3  wherein the core comprises cadmium and selenium. 
     
     
       7. A semiconductor nanocrystal in accordance with  claim 3  wherein the first shell comprises a Group IIB element and a Group VIA element. 
     
     
       8. A semiconductor nanocrystal in accordance with  claim 3  wherein the first shell comprises a Group IIB element and at least two Group VIA elements. 
     
     
       9. A semiconductor nanocrystal in accordance with  claim 3  wherein the first shell comprises zinc, sulfur, and selenium. 
     
     
       10. A semiconductor nanocrystal in accordance with  claim 3  wherein the second shell comprises a Group JIB element and a Group VIA element. 
     
     
       11. A semiconductor nanocrystal in accordance with  claim 3  wherein the second shell comprises at least two Group IIB elements and a Group VIA element. 
     
     
       12. A semiconductor nanocrystal in accordance with  claim 3  wherein the second shell comprises cadmium, zinc, and sulfur. 
     
     
       13. A semiconductor nanocrystal in accordance with  claim 1  wherein the semiconductor nanocrystal has a solid state external quantum efficiency of at least 95% at a temperature of 90° C. or above. 
     
     
       14. A semiconductor nanocrystal in accordance with  claim 1  wherein the semiconductor nanocrystal has a solid state external quantum efficiency of at least 90% at a temperature of about 100° C. 
     
     
       15. A semiconductor nanocrystal in accordance with  claim 14  wherein the semiconductor nanocrystal has a solid state external quantum efficiency of at least 95% at a temperature of about 100° C. 
     
     
       16. A semiconductor nanocrystal in accordance with  claim 1  wherein the semiconductor nanocrystal is undoped. 
     
     
       17. A semiconductor nanocrystal in accordance with  claim 3 , wherein the core comprises cadmium and selenium, the first shell comprises zinc, sulfur, and selenium, and the second shell comprises cadmium, zinc, and sulfur. 
     
     
       18. A film comprising semiconductor nanocrystals and a host material in which the semiconductor nanocrystals are dispersed, wherein the semiconductor nanocrystals included in the film emit green light having a peak emission with a full width at half maximum of about 30 nm or less when measured at a temperature of about 25° C. and when measured at a temperature of about 100° C.